Adding inference-friendly functions

[re-xyr]

For any function

f :: Eff es ~> Eff (es' ++ es)

we can have an alternative version of

f_ :: Suffix es es' => Eff es ~> Eff es'

that can work in many places without explicitly annotating types. However, the downside is that once inference fails, the type errors are harder to read and supplying type arguments is also harder.

There are 3 kinds of combinators in cleff:

1. Trivial handling combinators
2. Interpretation combinators
3. HO unlifting combinators

Only class (3) cannot be chained and therefore are safe to use the inference-friendly versions as default. Class (2) is very often chained but not class (1) or (3); in fact class (3) couldn't possibly be chained, and only very bizarre scenarios will require chaining class (1). Therefore the expected changes are:

• Add interpret_, interpose_, replace_ as inference-friendly versions of existing functions
• Change the signature of HO combinators toEff, toEffWith and withFromEff to be inference-friendly
• Change the signatures of raise and subsume to be inference friendly, renaming the original versions to be raise1 and subsume1

This will be a breaking change (though minimal breakage expected), and will hopefully come after another two three minor revisions (#17, #19, #21).